LOCATION SWEDESFLAT CAEstablished Series
TAXONOMIC CLASS: Loamy, mixed, active, thermic, shallow Ultic Haploxeralfs
TYPICAL PEDON: Swedesflat cobbly fine sandy loam, on a northeast facing 10 percent slope under a cover of annual grasses, forbs, blue oak, and scattered foothill pine, whiteleaf manzanita, buckbrush and Pacific poison oak at an elevation of 1450 feet, (442 m). When described on 8/9/1999 the soil was dry throughout. (Colors are for dry soil unless otherwise noted)
A--0 to 2 inches, (0 to 5 cm); very pale brown (10YR 7/4) cobbly fine sandy loam, yellowish brown (10YR 5/4) moist; 14 percent clay; weak very fine and fine subangular blocky structure; soft, very friable, nonsticky, nonplastic; many very fine roots; many very fine, fine, and medium tubular pores; 10 percent subangular gravel and 15 percent subangular cobbles; slightly acid, pH 6.3 by Hellige-Truog; clear wavy boundary. (1.5 to 4 inches, (2.8 to 10 cm) thick)
ABt--2 to 8 inches, (5 to 20 cm); light yellowish brown (10YR 6/4) cobbly sandy loam, yellowish brown (10YR 5/4) moist; 14 percent clay; weak fine subangular blocky structure; soft, very friable, nonsticky, nonplastic; many fine roots; many very fine, fine, and medium tubular pores; 3 percent patchy faint clay films on surfaces along pores and 3 percent patchy faint clay films on surfaces along root channels; 2 percent fine spherical reddish yellow (5YR 6/8), oxidized iron masses; 10 percent subangular gravel and 15 percent subangular cobbles; slightly acid, pH 6.3 by Hellige-Truog; clear smooth boundary. (3 to 6 inches, (8 to 15 cm) thick)
Bt--8 to 12 inches, (20 to 30 cm); strong brown (7.5YR 5/6) sandy loam, strong brown (7.5YR 4/6) moist; 18 percent clay; moderate fine and medium subangular blocky structure; moderately hard, very friable, slightly sticky, slightly plastic; few very fine roots; many very fine, fine, and medium tubular pores; 7 percent patchy faint clay films on faces of peds; 5 percent subangular gravel; moderately acid, pH 6.1 by Hellige-Truog; clear wavy boundary. (4 to 9 inches, (10 to 23 cm) thick)
Crt--12 to 18 inches, (30 to 46 cm); weakly cemented quartz diorite bedrock; few fine roots 40 percent clay films in fractures; clear wavy boundary. (3 to 6 inches, (8 to 15 cm) thick)
Cr--18 inches, (46 cm); weakly cemented quartz diorite bedrock; few fine roots top of horizon.
TYPE LOCATION: Butte County, California; about 1.5 miles west of Hurleton, California, approximately 500 feet south and 1600 feet west of the northeast corner of Section 21, Township 19 N., Range 5 E., 39 degrees, 29 minutes, 48 seconds North latitude and 121 degrees, 24 minutes, 46 seconds West longitude: NAD83-U.S.G.S. Quad: Bangor, California.
RANGE IN CHARACTERISTICS: Depth to paralithic bedrock is 10 to 20 inches, (25 to 51 cm). The mean annual soil temperature is 59 to 63 degrees F, (16 to 17 degrees C). The soil moisture control section is dry in all parts from about June through October (about 165 days). The particle-size control section averages 15 to 25 percent clay, 4 to 25 percent gravel, and 0 to 5 percent cobbles. Mineralogy is mixed. Rock fragments on the surface range from 0 to 3 percent stones.
The A horizon dry color is 10YR 5/3, 7/4, 7.5YR 4/4, 4/6 or, 5/4. Moist color is 10YR 3/4, 5/4, 7.5YR 3/4 or 4/4. Texture is loam, gravelly loam, sandy loam, gravelly sandy loam, fine sandy loam or cobbly fine sandy loam. Clay content ranges from 12 to 20 percent. Rock fragments range from 2 to 30 percent gravel and 0 to 15 percent cobbles. Base saturation by sum of cations ranges from 50 to 70 percent. Organic matter ranges from 2 to 8 percent. Reaction ranges from strongly acid to neutral.
The ABt horizon dry color is 10YR 6/4, 7.5YR 5/4, 5/6 or 6/4. Moist color is 10YR 5/4, 7.5YR 4/4 or 4/6. Texture is loam, gravelly loam, sandy loam, gravelly sandy loam or cobbly sandy loam. Clay content ranges from 13 to 20 percent. Rock fragments range from 5 to 35 percent gravel and 0 to 15 percent cobbles. Base saturation by sum of cations ranges from 40 to 60 percent. Organic matter ranges from 1.5 to 3 percent. Reaction ranges from moderately acid to slightly acid.
The Bt horizon dry color is 10YR 5/3, 5/4, 7.5YR 5/4, 5/6 or 5YR 5/8. Moist color is 7.5YR 3/4, 4/4, 4/6 or 5YR 4/6. Texture is gravelly loam, sandy loam, gravelly fine sandy loam, sandy clay loam, or gravelly sandy clay loam. Clay content ranges from 18 to 25 percent. Rock fragments range from 0 to 30 percent gravel. Base saturation by sum of cations ranges from 40 to 74 percent. Organic matter ranges from 0.2 to 1.5 percent. Reaction ranges from moderately acid to neutral.
COMPETING SERIES: There are no other series in this family.
GEOGRAPHIC SETTING: Swedesflat soils are on ridge tops and side slopes on plutons in Sierra Nevada foothills. Slopes range from 2 to 30 percent. These soils formed in residuum from intrusive igneous rocks, mainly quartz diorite. Elevation is 500 to 2200 feet, (152 to 671 m). Mean annual precipitation is 30 to 50 inches, (762 to 1270 mm). The mean annual temperature is 57 to 60 degrees F, (14 to 16 degrees C). Frost free season is 235 to 260 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Flanly, Hurleton, Parkshill and Rackerby soils. Flanly soils are moderately deep to a paralithic contact. Hurleton soils are moderately deep to paralithic contact and are loamy-skeletal. Parkshill soils are very deep. Rackerby soils are shallow to paralithic contact and are loamy-skeletal.
DRAINAGE AND PERMEABILITY: Well drained; low to medium runoff; moderately rapid to moderate saturated hydraulic conductivity in the A and ABt horizons and moderate in the Bt horizon.
USE AND VEGETATION: This soil is used for livestock grazing, wildlife habitat, watershed, and home site development. Vegetation is ripgut brome, red brome, blue oak, interior live oak, scattered foothill pine, whiteleaf manzanita, toyon, buckbrush, and Pacific poison oak.
DISTRIBUTION AND EXTENT: Butte County, California and occurs in (M261Fb) Lower Foothills Metamorphic Belt subsection of the (M261F) Sierra Nevada Foothills section. MLRA 18-Sierra Nevada Foothills. The soils are not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Butte County, California 2005. Source of name is from Bangor Quadrangle.
REMARKS: These soils were previously mapped as Sierra sandy loam, (SI) and Rough broken and stony land, (Rb) in the Soil Survey of Oroville Area, California 1926.
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - zone from 0 to 8 inches, (0 to 20 cm) (A and ABt)
Argillic horizon - zone from 8 to 12 inches, (20 to 30 cm) (Bt)
Particle-size control section - zone from 0 to 12 inches, (0 to 30 cm) (whole soil)
The soil moisture control section - zone from 8 to 12 inches, (20 to 30 cm).
Paralithic contact - at 12 inches, (30 cm).
Base saturation - assume sum of cations is less than 75 percent in one or more subhorizons within 30 inches, (75 cm) or paralithic contact, whichever is shallower.
Cation-Exchange Activity Class - assume ratio of ammonium acetate at pH 7 to clay is 0.40 to 0.60.